Definition

Self-satisfied, conceited; ingratiating in an oily way.

Commentary

Etymology

Smarm originally meant to smear (especially in the sense of slicking down with something like hair cream or oil) (NSOED), but now is used mostly in the sense of behaving in an oily way - that is, with a lot of overdone flattery and deference. In the U.S. we'd say "suck up" rather than "smarm up".